November Imaging Session: IC 5146, NGC 1333, NGC 2174, IC 405

11/3/23 Starting a new target: IC 5146 is a reflection/emission nebula and Caldwell object in the constellation Cygnus. 

Clear dark sky forecast for 11/3 showing clear skies until around 3am with average seeing.

Astronomy Seeing forecast for 11/03 from meteoblue showing the arrival of peak clouds around 2am.

Given the radius of about 1 degree, using the Meade LX10 with the 0.63 focal reducer with the dual narrow band Ha/OIII filter with the new Svbony SV405cc OSC camera... with an expected low temperature of about 40 dgrees F, set the camera temperture to -5c.  After finding good focus on the Celestron 9x50 RACI finder with the ZWO ASI120MC-S, started with a rough focus on Sadulsud (Beta Aquarii) with the priimary OTA.  Then began polar drift alignment...initially way off at -1200" (ouch) (pre-meridian flip).  Tightened on the right side of the mount (facing the front). First adjustment: -700".  Then -200. Over-corrected on the third adjustment with ~100".  After significant back and forth, meridian flip, etc...finally achieved reasonable polar alignment.

The next challenge was achieving a final fine focus. Stumbled into a bug where the first image captured from the SV405cc was fine, but the subsequent frames were corrupted. Was unable to find an immediate solution, which ended collection for the evening.  :<  This issue was ultimately captured in an Indi/Ekos forum thread.

11/05/23 -- Reverted to a previous version of the indi-svbony ubuntu driver for arm64, which appeared to fix the problem with the SV405cc.  Stumbled into an additional problem with guiding...where the guide port on the Zwo ASI120MC-S was ineffective.  Reverted to using the mount with pulse guiding, which immediately fixed guide calibration errors.  Working towards collection against the bright nebula, NGC 1333.  Started with collection at 200s, then 300, finally set up the collection at 400s with the SV405cc camera cooled to 0 degrees with gain at 20.

Forecast for seeing on 11/5/23 from cleardarksky.

Forecast for 11/5/23 from meteoblue.

Results from this collection were poor with numerous guide issues -- but this could be due to clouds that started rolling in right as collect was really commencing.  Few usable frames came from the evenings' collection because of the guide errors (ultimately, clouds).

11/7/23 -- Attempt against IC 5146 for a few hours before it sneaks behind trees.  Re-checked polar alignment and no adjustments were needed with a polar alignment error under 6".  Re-focused (much warmer temperatures).  Noted problems with guide calibration and guide errors (with the internal guider in Ekos... did not note any issues with PHD2 running on the Odroid XU4 during the initial drift alignment testing).  Moved back and forth between pulse guiding with the mount vs using the guide port on the Zwo ASI120MC-S.  Ultimately noted a guide error of less than 2" in RA and DEC using the ST4  guide port as collection was underway.

Cleardarksky forecast for 11/07/2023 showing poor seeing, dark skies and no clouds.

Meteoblue seeing forecast for 11/07/23 with no moon until ~2am and no clouds. Seeing numbers look poor here as well.

Ekos when capture against IC1546 just started showing reasonable guide numbers and an initial single 400s frame at gain 20 with nebulosity visible in the center.

Used ASTAP to make initial quality measurements and monitor the first few frames using stacking against darks (20x, 400s, gain 20, temp 0) and flats (20x, zenith pointing in the AM with paper towel).

Early result from frames 1-5 (33 minutes of integration) stacked in ASTAP using 20x darks and 20x flats collected earlier.

Collection against IC 5146 ended early at around 10:30pm as trees entered the frame. :<  Started a new job in the scheduler for NGC1333.  Set exposure time to 500s and gain to 30 based on histogram from teh IC 5146 frames which suggested longer integration and stronger gain could be helpful. After collecting six frames and zero useful signal appearing in ASTAP after initial stacking, switched to NGC2174 (Monkey Head Nebula) as a more achievable target for collection.

Early result from ASTAP stacking the first six frames from NGC 1333 (6x500s, 50 minutes) using the 20x 400s dark frames and the 20x flat frames from yesterday.

 

Initial result from stacking the frames 2-5 (4*500s, 33 minutes of integration) from NGC 2174 in ASTAP using the 20x 400s dark and 20x flat frames from yesterday.

A total of 32 frames were successfully collected overnight.

ASTAP based stack of all 32 frames using the previous nights 20x 400s darks (will need to be redone with proper 500s dark frames with the correct gain later).

Final version of NGC 2174 from Astro Pixel Processor using 15000s of integration.

11/8/23 -- poorer skies, but made an attempt for additional collection against IC 5146. Mount and OTA untouched since yesterday.  Initial plate solve and guiding successful with guide RMS of ~2.7".

Cleardarksky forecast for 11/08 with no hint of clouds but poor seeing predicted.

Meteoblue "seeing" forecast for 11/08 suggesting low clouds starting at 11pm.

By 10:20, trees appeared ending the collection session for IC 5146 with 39x400 light frames.

IC 5146 from 36x400s (4 hours) light frames from 11/07 and 11/08/2023, 20x400s dark frames and 20 flat frames stacked in ASTAP.

Final version of IC 5146 from Astro Pixel Processor which used 13,600s (3.77 hours) of collection.

Started new collection on IC 405 (Flaming Star Nebula). Performed an initial stack of the first 12x400s light frames with 20x400s dark and 20x flat frames in ASTAP.

IC 405 (Flaming Star Nebula) stacked with ASTAP from 44x400s (4.8 hours) lights, 20x400s dark and 20x flats with the LX10 using the Meade 0.63 focal reducer, the dual-narrow band (Ha/OIII) filter and the SV405CC at gain 20.

Final version of IC 405 processed with Astro Pixel Processor.

11/10/23 - Following rains with the OTA & mount covered, attempted additional collection on IC 5146. Started by rechecking the polar alignment with a drift test using PHD2 on the Odroid XU4. Started at -75" and tightened on the right side of the mount. Dropped to 51".  Eventually got this down to about -3".  By the time this was all sorted, IC 5146 had dropped below the tree line. Switched collection to IC 405.  

Seeing forecast for 11/10/23 from Cleardarksky with no indication of clouds.

Forecast for meteoblue for 11/10 indicating high level clouds creep in at ~11pm. :<

Ended up with 48x400s light frames from IC 405 over night with collection continuing through to 4:41am.  Triage in ASAP with basic metrics and quick stacking suggested a significant shortfall in quality (and number of stars) after ~1am.  Processed these through Astro Pixel Processor to update the Flaming Star Nebula result.

IC 405 (Flaming Star Nebula) processed from 3 nights of imaging totaling 82x400s (32800s, ~9 hours)

11/11/23 - Clouds again look grim in forecasts, but skies (visually) look good at ~8pm... so with the mount still unmoved... started a session just to see what could be collected.  Performed an initial focus check against Deneb using the Bahtinov mask...which seemed to indicate a good focus. 

1x10s exposure on Deneb at gain 20 through the LX10 with the 0.63 focal reducer plus the dual-narrow-band filter (Ha/OIII) with the SVBony 405cc at gain of 20 through a Bahtinov mask. Since the central spike is centered, this suggests good focus.

Set up the scheduler for IC 5146  (40 light frames) then IC 405.  Ultimately, this resulted in only seven light frames for IC 5146 before hitting trees. Over the rest of the evening, 36 additional light frames were collected for IC 405.  The Analysis tool in Ekos indicated a gap in guiding between 2:13 and 3:28am likely due to clouds.  This was reflected in a gap in collected files.  Guiding resumed until 3:47am and the session was scheduled to end at 4am. The job ended nominally with the mount parked and the camera chiller turned off.

Initial triage / analysis using ASTAP showed one early collection (11:03pm from 11/11) with poor guiding (failed to co-register) and the final three collections (3:40-3:57am on 11/12) as exceptionally poor (few stars visible) with quality score of 0.  

IC 405 (Flaming Star Nebula) from the 34x400s light frames collected on 11/11/23 in an initial stack computed with ASTAP.

AstroPixelProcessor analytic results for the 103x400s IC 405 light frames spanning three sessions (11/08, 11/10 and 11/11) used in the final stacked result.

Additional frames from across the three sessions were discarded in AstroPixelProcessor (APP) (version 2.0.0-beta22) after they failed registration or had extremely low quality score leaving 103x400s (41,200 seconds, 11.4 hours) total for integration. Analytic results from APP show how the quality of collection starts high each evening and drops towards morning...based on weather forecasts this seems likely largely due to increased high level clouds...although the sky background statistic from this tool seems flat across each session.

Final IC 405 stack in AstroPixelProcessor with 103x400s (41,200 seconds, 11.4 hours)